Deposits (Certificates of Deposit) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Deposits [Abstract]
Time Deposit Maturities, Next Twelve Months	$ 57,795us-gaap_TimeDepositMaturitiesYearOne
Time Deposit Maturities, Year Two	7,340us-gaap_TimeDepositMaturitiesYearTwo
Time Deposit Maturities, Year Three	5,463us-gaap_TimeDepositMaturitiesYearThree
Time Deposit Maturities, Year Four	1,968us-gaap_TimeDepositMaturitiesYearFour
Time Deposit Maturities, Year Five	4,239us-gaap_TimeDepositMaturitiesYearFive
Total Time Deposit Maturities	76,805dnbf_TotalTimeDepositMaturities
Brokered Deposit Maturities, Year Two	4,005dnbf_BrokeredDepositMaturitiesYearTwo
Brokered Deposit Maturities, Year Three	6,233dnbf_BrokeredDepositMaturitiesYearThree
Brokered Deposit Maturities	10,238dnbf_BrokeredDepositMaturities
Total Deposit Maturities, Next Twelve Months	57,795
Total Deposit Maturities, Year Two	11,345dnbf_TotalDepositMaturitiesYearTwo
Total Deposit Maturities, Year Three	11,696dnbf_TotalDepositMaturitiesYearThree
Total Deposit Maturities, Year Four	1,968dnbf_TotalDepositMaturitiesYearFour
Total Deposit Maturities, Year Five	4,239dnbf_TotalDepositMaturitiesYearFive
Total Deposit Maturities	$ 87,043dnbf_TotalDepositMaturities

Brokered Deposit Maturities

No definition available.

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- Definition

Brokered Deposit Maturities, Year Three

+ References

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Brokered Deposit Maturities, Year Two

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- Definition

Total Deposit Maturities

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- Definition

Total Deposit Maturities, Next Twelve Months

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- Definition

Total Deposit Maturities, Year Five

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- Definition

Total Deposit Maturities, Year Four

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Total Deposit Maturities, Year Three

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Total Deposit Maturities, Year Two

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- Definition

Total Time Deposit Maturities

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- Definition

Amount of time deposits maturing in the fifth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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Amount of time deposits maturing in the fourth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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Amount of time deposits maturing in the next fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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Amount of time deposits maturing in the third fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

+ References

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Amount of time deposits maturing in the second fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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